heating & air conditioning

Preventive Maintenance FAQ


Why should I perform preventive maintenance?

  • Heating and cooling systems work incredibly hard heating and cooling your households. The constant stopping, starting and continual operations can wear down a machine quickly and unexpectedly if the proper care and maintenance is delayed. However, by performing preventive services on your systems seasonally, you can maximize the life cycle of your heating and cooling and guard against many unexpected failures.

What equipment requires preventive maintenance?

  • Once a year, seasonally, Gas furnaces, Gas Boilers, Oil Furnaces, and Oil Boilers, Electric heat, Heat Pumps and air conditioners require professional Preventive Maintenance cleanings.
  • Inspections on Gas furnaces, Boilers & Electric Heaters should include checking ductwork, pipes, dampers, valves, the chimney, registers, thermostats, radiators, pumps, blowers, fuel lines, the gas meter, replacing or cleaning filters, and checking the mechanisms of the Furnaces and Boilers.
  • Inspections on Oil Furnaces and Boilers include cleaning and adjusting electrodes, replacing nozzles needed, checking tubes and end cones, checking thermostats, clean stack relays, clean CAD cell, cleaning pump strainers, checking pump pressures, checking oil line fittings, cleaning heat exchangers, inspecting heat exchangers, cleaning flues & vents, and replacing oil filters.
  • Inspections on Heat Pumps, also include checking the defrost controls, emergency heat, coils and outdoor thermostat.
  • Inspections on Air Conditioning Units, also include the inspections of the fans, coils, drains, thermostats, refrigerant lines and checking the mechanisms of the Compressors.

What is a low blow?

  • When servicing the distribution side of a forced-air system, you begin with the blower. In this phase, the axle will be lubricated, blades cleaned and the lower motor checked to ensure that your system is not being unnecessarily burdened.
  • During a low blow, the fan belt should be adjusted to deflect no more than one inch when pressed and all accessible duct joints should be sealed. Ducts running outside heated spaces should all be insulated.

What type of filter should I use?

  • Standard furnace filters work well to keep your system and its ductwork clean, but they don?t really improve indoor air quality. To do that you need a media filter. The media filter rests between the main return duct and the blower cabinet and will improve dust and particle removal by seven times that of a standard furnace filter. However, upgrading to a pleated media filter will remove everything from insecticide dust to airborne viruses from the filtered air.
  • A media filter can have a life exceeding two years, and its only drawback is that its tight fiber weave can cause your furnace to have to work harder to blow air through the house. Always choose a filter that matches your blower?s capacity.

What are the preventive maintenance measures for my ducts?

  • Although modern technology has made significant advances in air filters over the past decade, a fractional amount of dust still finds its way past heating and cooling filters and into your home?s ducts. As this dust accumulates throughout your home, it creates the perfect environment for the growth of mold, mites and harmful bacteria. To check your ducts for dust buildup, pull off several supply and return registers and see how much dust has accumulated in the system. If you choose to clean your system, your best option is to contact a professional duct cleaner.
  • Although duct cleaning has little effect on the actual air quality, it will eliminate a house-wide breeding ground for harmful bacteria and mold in addition to helping your heating and cooling system operate more efficiently. If you are installing a new system, you should consider cleaning the ducts at the same time. New systems are often more powerful than old systems and can stir up dust that is sitting in the existing ductwork.

What is the most efficient way to run my heating and cooling system?

    Here are several tips to help you keep your system running at its most efficient level:
  • Have preventative maintenance cleaning professionally performed seasonally on both your systems.
  • Change your filters every month.
  • Keep your thermostat at a constant temperature; the recommended temperature is 78°, even when no one is home.
  • Check the outside condensing unit for any grass clipping or leaves stuck to the coil or dirt.


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Ardmore, Aston, Berwyn, Boothwyn, Broomall, Bryn Mawr, Chadds Ford, Chester Springs, Coatesville, Devon, Downingtown, Exton, Glen Mills, Glenmoore, Havertown, Kennett Square, Malvern, Newtown Square, Paoli, Thorndale, Thornton, Villanova, Wayne and West Chester
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